Rex (voice)
Original Film Writer
Harold Jenkins
John Fate (voice) (1 episode)
Father Francis Ignatius (10 episodes)
Cyrus Rose (1 episode)
Humphrey (voice) (1 episode)
Mr. Mustela (voice)
Mort Rifkin
William Badpastor (2 episodes)
Mr. Crocus
Rex (voice)
Rex (voice)
Wallace the Hernia (voice) (1 episode)
Jyle (voice) (1 episode)
Dr. Derek
Charles Lester (5 episodes)
John Sturgis (53 episodes)
Herb Smith (2 episodes)
Jerry North (3 episodes)
Mr. Williams (1 episode)
Principal Miller
Mr. Woodley (voice)
Evil Brain (voice) (1 episode)
Tall (voice) (5 episodes)
Mr. Neville (1 episode)
Kliegler
Mr. Willis
Gary the Gadget Guy (voice)
Winslow Elliott (6 episodes)
Rex (voice)
Eustace Bagge
Kenneth Walters (1 episode)
Wallace Shawn (voice) (1 episode)
Halvard Solness
Producer
Translator
Screenplay
Not-So-Magic-Mirror (voice) (1 episode)
Saul (voice)
Saul (voice) (1 episode)
Dr. Fieldman
Mr. Papadopoulos
Rex (Voice)
Clarence
Charles Lester (3 episodes)
Gideon Rosen
Rex (voice)
Dr. Van Helsing
Rat King (voice) (1 episode)
Rex (voice)
Dr. Warren Hughes (3 episodes)
Rex (voice)
Calico (voice)
Rex (voice)
Dr. Christian Burr (uncredited)
Rex (voice) (3 episodes)
Sterling Biddle (1 episode)
Booker / Broker / Lancealot Squarejaw
Broker / Booker / Lancelot Squarejaw
The Sorcerer (1 episode)
Roy Batters (1 episode)
Benjamin Edelman (1 episode)
Cyrus Rose (11 episodes)
Mr. Gibbles (voice)
Mr. Gibson
William Halsey (4 episodes)
Baron Von Westphalen
Screenplay
Author
Math Teacher (uncredited)
Munk (voice)
Billy (voice)
Film Professor (1 episode)
Barnacle Paul (voice)
Principal Fetchit (voice)
Lonny Moon (1 episode)
Dr. Von Oy (1 episode)
Gilbert Huph (voice)
Martin Gable (1 episode)
Screenplay
Principal Crosby Strickler (voice)
Clinic Doctor
Herman
Colonel Wilson
Mimir
Mr. Gelb
Howard Stiles (8 episodes)
Rex (voice) (uncredited)
Bertram (voice) (3 episodes)
George Bond
I.E. Shinn (2 episodes)
Mr. Dune (1 episode)
Principal Strickler (voice) (47 episodes)
Rex (voice)
Tarzan Chimp (voice)
Furnaceman
Philip Ny (voice) (1 episode)
Theatre Play
Writer
Arthur Blake
Cosmo
Victor Finley
Labrador MC (voice)
Rex (Voice) (55 episodes)
Rex (voice)
Stan Spiegel
Mr. Wendell Hall
Echidna (voice)
Canadian Prime Minister Clark MacDonald
Boss Man (voice)
Principal Mazur (voice)
Charles Haste (1 episode)
Horatio Byrd
Boss Man (voice) (60 episodes)
Mr. Little
Doctor/Therapist
Cashpot
Sibor, Semage's Beau
Everett Willits
Simon Carr
Translator
Dr. Fishbinder
Oiseau
Jeffrey Engels (5 episodes)
Vizzini
John Lahr
Masked Avenger
Henderson's Attorney
Mike Hoover
Father Abruzzi
Dr. Elliot Fibel
Professor Silverfish
Mr. Pardon
Turtle
Frank Judd
Harold DeVoto
Jules Goldfarb
Otto Jaffe
Arnie Ross (1 episode)
Arnie (1 episode)
Oliver
Birthday Party Guest (uncredited)
Wallace Shawn
Writer
Waiter
Eric Van Dongen
Assistant Insurance Man
Workshop Member
Jeremiah
Writer